[PROJ] Odd 6.3.0RC1 issue

[Roger Bivand]

Having installed 6.3.0RC1 and built GDAL 3.0.2 and GDAL master against it, 
I'm seeing a possible regression in GDAL function exportToProj4() after 
instantiating with EPSG:27700. With 6.2.1 I see "+proj=tmerc +lat_0=49 
+lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +units=m 
+no_defs" but with 6.3.0RC1 and both GDAL versions "+proj=tmerc +lat_0=49 
+lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +no_defs". The 
offending code is on R-Forge at: 
https://r-forge.r-project.org/scm/viewvc.php/pkg/R/ogr_sp.R?view=markup&root=rgdal
function showSRID(), calling C++ function P6_SRID_show() at 
https://r-forge.r-project.org/scm/viewvc.php/pkg/src/ogr_proj.cpp?view=markup&root=rgdal.

In the failing case, importFromEPSG() seems to work, but for 6.3.0RC1, the 
string exported to Proj4 has lost +ellps= and +units=.

I imagine that this is my mistake, but help would be appreciated.

Roger

-- 
Roger Bivand
Department of Economics, Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; e-mail: Roger.Bivand at nhh.no
https://orcid.org/0000-0003-2392-6140
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